Moved game, now game data incomplete. Will I lose gameplay if I redownload packs

@N3mo04  As long as you don't save your progress with certain packs missing, your saves should be intact, and all the data should be back once your packs are restored as well.  At worst, you might have to load a backup save rather than the most recent version, but again only if you saved with the packs missing.

https://sims4.crinrict.com/eng/2014/09/save-games/#wiederherstellen

It's a good idea to backup your save files anyway, now and in general, because you never know when you might need to restore a backup.

For the packs not loading, try repairing the game in Origin: open your game library, right-click on the Sims 4 icon, and select Repair.  If that doesn't help, clear Origin's cache:

https://help.ea.com/en-us/help/faq/clear-cache-to-fix-problems-with-your-games/

restart your computer, and repair again.  It may also be that the packs need to be redownloaded (even though you can see them), but that may start automatically after you clear Origin's cache, or after you've launched the game a couple of times.  You can always check to see whether the content is loading by starting a new save, rather than loading one of your existing saves.